Pursued by detectives, Johnny Walters leaves the city to visit his family in a small California town. Among the household: his dead brother's luscious widow Helen, who soon is attracted to him. Ominous events and conflicting evidence leave Helen suspicious, but uncertain about her brother-in-law as tension builds...

A movie serial in 13 chapters, and Lionel Atwill's final film: Following the end of WWII, war-monger Sir Eric Hazarias sets the wheel in motion for WWIII. His search for Meteorium 245, the only practical defence against the atomic bomb, leads him to mythical Pendrang. Obstructing his sinister plan to rule the world are Rod Stanton, United Peace Foundation investigator, Tal Shan , Pendrang native, and Marjorie Elmore, daughter of scientist Dr. Elmore, unwilling assistant to Sir Eric.

Soon after a young woman breaks off her engagement to a doctor, the doctor is found murdered. Suspicion falls on his ex-fiancé and a pilot with a checkered past.

Government agents work to interfere with schemes to trick the Comanches into war with the Texans.

In time-honored fashion, a couple of supporting players -- George Dolenz and Bill Kennedy -- found themselves elevated to starring roles in this minor Universal serial. They played Royal Canadian Mounted Police officers investigating the murder of a miner. The story, of course, was less important than speed and action, which directors Ray Taylor and Lewis D. Collins delivered in typical slap-dash Universal style. Starlet Daun Kennedy did not make much of an impression as the imperiled leading lady, and former star Robert Armstrong (of King Kong fame) was wasted in a subordinate role. Rondo Hatton, a non-actor whose grotesque appearance (caused by acromegaly, the so-called "Elephant Man" disease) was tastelessly exploited by Universal in the '40s, appeared as one of the outlaws.

"An average American family", the Middletons, visit the 1939 World's Fair and witnesses the advent of future technology, encountering robots and dishwashers for the first time.